KB Performance

KB Performance specializes in advanced forged and hypereutectic piston technology designed to meet the demands of modern Harley-Davidson engine builds. The brand’s extensive lineup of motorcycle piston kits covers popular configurations including Twin Cam big bore pistons, Evolution engine pistons, Sportster 883 to 1200 conversion pistons and Milwaukee-Eight big bore piston kits. Each design is carefully engineered to deliver balanced compression, controlled expansion and reliable ring seal for long-term engine durability.

Engine builders choose KB Performance pistons for their precise machining and application-specific compression ratios that support both stock and modified cylinder heads. From 95”, 103” and 110” Twin Cam builds to large-displacement M8 114”, 117”, 124” and 128” big bore conversions, KB piston kits help optimize combustion efficiency and throttle response. These pistons are well-suited for performance upgrades where strength, heat control and consistency are critical.

In addition to complete piston kits, KB Performance offers essential engine assembly components such as wrist pin lock rings and installation hardware to support accurate and repeatable engine assembly. Whether refreshing a stock engine or building a high-compression performance setup, KB Performance delivers motorcycle pistons that align with professional engine-building standards and proven real-world results.